Question

Which relation is a function?

O {(1, 2), (2, 1), (1, 3), (3, 1)}
O {(1, 2), (2, 3), (3, 4), (4, 5)}
O {(1, 2), (3, 4), (5, 6), (1, 8)}
O {(0, 2), (0, 4), (0, 6), (0, 8)}

Answer 1

The second relation is a function.

For a relation to be a function, each x-value can only have a singular corresponding y-value. Since all other relations feature x-values with multiple y-values, the second relation is a function.